Cutting edge nanoparticle research by scientists at King Abdullah University of Science and Technology (KAUST) among others has been published in the prominent journal, Organic Letters, a publication of the American Chemical Society.

The paper entitled "Snap-Top Nanocarriers" was published in August and has already been cited in several nano-scale focused drug delivery publications.

A team from Northwestern University, Illinois, the University of California, Intel Labs and King Abdulaziz City for Science and Technology (KACST), including some who subsequently joined the KAUST Controlled Release and Delivery (CRD) laboratory – now part of the university's Advanced Membranes and Porous Material Center - carried out extensive research to come up with a new and unique integrated system of controlled drug delivery.

Dr. Niveen M. Khashab, a Chemical Science Assistant Professor at KAUST and a co-author on the paper, said: “To have this work published was a great honor and is testament to the good work put in by my colleagues.

"The main goal behind our pharmaceutical and drug delivery work here is to have control over the delivery of the drugs within the body. There are enough drugs out there that kill cancer cells effectively, however these target all of the body’s cells and patients have to suffer because of it."

Along with their partners around the globe, Dr. Khashab and her team, currently at KAUST, have developed a new means of delivering drugs within the body on a nano-scale.

The controlled delivery in this system is achieved through its inherent design in which disulfide linkage breaks only in the presence of those specific agents that are over expressed in cancer cells. Glutathione, a natural antitoxin produced by the body to protect cells from infection, has the effect of reducing the disulfide linkage and triggers the system to open and deliver the drug.

The system is prepared using a modular approach that allows for the piecing together of building blocks which extend outwards from mesoporous silica nanoparticles (MSNP).

Dr. Khashab explains: “You put your drug inside the module, like filling a can with soda, then you cap it, and once this cap is opened the contents are released.

"Once the module enters the body it then focuses on killing cancer cells. This 'killing' doesn't happen unless you have a stimulus, like someone opening a can. In this case the stimulus causes the breaking of the disulfide linkage.

"Now, that happens in the body with glutathione. This (glutathione) is over expressed in cancer cells, for example, so your can will not open until it is in a cancer cell because the opening only happens with material that is found abundantly in those specific cells.

"This gives us cell-specific targeting and complete control over the release of the drug, thus killing just the cancer cells and not normal tissue.”

Cancer treatment such as chemotherapy kills cells that divide rapidly. Because of this epithelial cells are among the first to go, and since hair and stomach lining are epithelial, alopecia (hair loss), sickness and diarrhea are all side effects of the treatment. Using controlled and targeted delivery can provide a solution for all these unwelcome side effects.

Dr. Khashab hopes to eventually commercialize the drug delivery system at KAUST so that it can be used to benefit patients around the world.

She said: "In the future, I would like to see these capsules used as a replacement for some treatments. So, for example, instead of receiving chemotherapy at a hospital you can just take a pill and that would be your therapy for the day."

Further Information

• KAUST Controlled Release and Delivery laboratory
• Dr. Niveen Khashab biography